Illuminating device



Feb. 23, 1937. L. R. PETERS ILLUMINATING DEVICE Filed Aug. 20, 1932 2 Sheets-Sheet 1 [NI/EMT UR LED R.PE TERS,

H15 ATTUANEY Feb. 23, 1937. PETER; 2,071,948

ILLUMINATING DEVI CE Filed Aug. 20, 1932 2 Sheets-Sheet 2 [NI/EN T UH LEUR. PE TEAS,

[7'15 .ATTQANEY Patented Feb. 23, 193'? PATENT OFFICE 'ILLUMINATING DEVICE Leo R. Peters, Cleveland, Ohio, assignor to General Electric Company, a corporation of New York Application August 20, 1932, Serial No. 629,637

2 Claims.

My invention relates to illumination and illuminating devices and more particularly to an illuminating arrangement comprising a string of electric lamps. One of the objects of my invention is to provide a string of lamps, such as Christmas tree strings, particularly adapted to decorative use, which will be of simple and inexpensive construction and a method of manufacture of such a string. Another object is to provide an improved means of electrical connection providing for the use of a plurality of strings of lamps at one time.

According to my invention, a plurality of electric lamps, each comprising a bulb enclosingan electric light source, are connected by conductors, each of which extends from a lead wire of one lamp to a lead wire of the next lamp. A body of plastic material is then molded and hardened on each of the bulbs, enclosing a portion of the bulb and the connections between the lead wires and conductors to form a permanently interconnected string of lamps, thus dispensing with the usual sockets and bases which have been heretofore used.

In the drawings Fig. 1 is a sectioned elevation of a lamp comprising my invention; Fig. 2 is an elevation of apparatus used in the construction of said lamps; Fig. 3 shows a string of lamps in series; Fig. 4 is a perspective view of a terminal box; Fig. 5 is a perspective view of the terminal box assembly; Fig. 6 is a partly sectioned side view of a modified lamp; and Fig. 7 shows a string of said modified lamps in series.

Referring to Fig. l the lamp comprises a bulb i0 having a filament ll therein mounted on inner lead wires l2 which pass through the neck i3 of said bulb and terminate in outer lead wires H which may be bent to extend at substantially right angles to said neck portion It. The inner 40 lead wires l2 are suitably supported and spaced by a glass bead i5 fused around portions thereof. Ends of conductors it which preferably consist of a plurality of wire strands and an insulating covering i1, are placed over or at least in contact 5 with the ends of the outer lead wires H and a base I! of a plastic material or compound is molded around the bulb neck ll, cuter lead wires l4 and the said ends of conductors It. The extreme ends of the wires comprising the conductors 50 II are preferably bent back as shown in the drawings, to insure a flrm Joint with the material of the base IS.

The molded material forming the base is preferably composed principally ,of a synthetic resin.

u ahardeningcompoundandafillersuchasmarble flour or the like. There are a number of such synthetic resins such as bakelite. One such synthetic resin which has produced good results is commercially known as Durite which is a furfural or phenol formaldehyde product. This material 5 is mixed with a hardening compound such as hexamethylenetetramine and a filler which is non-compressible. An inorganic material such as alumina, magnesia or silica will serve as a filler but marble flour is preferred. 10

The method of molding the base of the lamp shown in Fig. 1 consists, as shown in Fig. 2, in placing the bulb ill in a suitably shaped seat I! in a support 20. The ends of the conductors it are slipped over the ends of the outer lead wires 15 I4 and the two halves of a mold 2! are placed around the neck l3 of the bulb with the conductors l6 extending through grooves 22 therein. The requisite amount of molding material is inserted into the passage 23 and is forced into the mold by a plunger 24 under a pressure of from fifteen to one hundred fifty pounds per square inch, preferably about fifty pounds per square inch. The mold is now heated, preferably to 165 C., until the base material has taken a permanent set.

In Fig. 3 is shown a string of lamps in series which are adapted to decorative use such as Christmas tree lighting. The ends of said string may terminate in plugs 24-25 adapted to. plug into a terminal box 26 (Fig. 4). Said terminal 30 box permits the connection of a number of strings of lamps to a main feeder line 21 terminating in a plug 28 which fits into a standard slotted receptacle. Referring to Fig. 5, said terminal box comprises the body 26 having two 35 parallel rows of holes 29-30 in the top thereof which communicate with two slots 3l-32 extending to the bottom of said body. Said slots 3l32 are adapted to receive bus bars 33- which are provided with spring fingers SL-SG respectively. Said fingers 35-36 have oppositely disposed inwardly curved portions 31-" adapted to receive and grip the plugs 24-25 which are inserted therein through the holes 28-30. The bus bars 31- are connected to each of the wires comprising the line 21 which passes through a hole I! in one end of the body 26 and are held in the slots 3l-32 by a cover plate 40. The rows of holes 29-30 may be of different sizes to receive plugs 24-25 of different sizes to insure making the proper connections. Thus it is impossible to connect both ends of the string of lamps to the same bus bar. The slots Il-I2 and the respective bus bars 33- are correspondingly made of diflerent widths.

In place or the lamp shown in Fig. 1, my invention may be applied to a double-ended lamp of the form shown in Fig. 6 which comprises an elongated bulb 4| having a filament 42 therein mounted on lead wires 43 each of which extends through one of the ends 01' said bulb. Ends of conductors 44 which preferably consist of a plurality of wire strands and an insulating covering 45 are placed over or at least in contact with the ends of the outwardly projecting portions of the lead wires 43. The extreme ends of the wires comprising the said conductors 44 are preferably bent back the same as in the construction of Fig. 1. material or compound which may be the same as that used for the base of the lamp oi! Fig. 1, is molded around each oi! the ends of the bulb 4|, outside portions of lead wires 43 and the ends of conductors 44. Fig. 7 shows a string of such lamps connected in series and terminating in plugs 4148 which may be used in conjunction with the terminal box 26 of Fig. 4.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. An electrical device comprising a bulb, an

A base 46 of a plastic electric light source enclosed therein, a leadingin wire connected to said source and extending exteriorly oi! said bulb, an insulated conductor having an end electrically connected to the outer end of said leading-in wire and an end portion of said insulation being folded back and extending transversely of said conductor and a body of plastic material molded and hardened around the conductor and leading-in wire and the adiacent portion oi! the insulation and said bulb.

2. An electrical device comprising a bulb, an electric light source enclosed therein, a leadingin wire connected to said source and extending exteriorly of said bulb, an insulated conductor comprising a plurality of strands of wire, the end of said leading-in wire being disposed amidst the strands of wire at an end of said conductor and the extreme ends of said strands of wire and insulation being folded back, said strands of wire being spread radially outward and a body of plastic material molded and hardened around a portion of the bulb and the adjacent ends of leading-in wire and conductor.

LEO R. PETERS. 

